Birth control and period

I started birth control again recently..just finished my first pack. I had my period 9 days earlier than it was supposed to be and before the sugar pill week. Not a big deal for me but ever since then randomly there will be dark brown spots on the toilet paper like when you’re coming off your period. It’s random and never a big clot or anything. I don’t remember this when I was on the pill last time. Has anyone else had this? I have an appointment with women’s health on the 10th for an annual and was gonna bring it up if I needed to